Liquid-fuel burner



W. O. HORNE March 25, 1930,

LIQUID FUEL BURNER 2 Sheetsf-Sheet l W. O. HORNE March 25, 1930.

LIQUID FUEL BURNER Y Filed Aug. 19, 1925 2 Sheets-Sheet 2 Zzyar WILL/AM 0. HORNE zzgrneg/ Patented Mar. 25, 1 930 OFFICE -WIl'lIIAllLE 0. BORNE, 0F MINNEAPOLIS, MINNESOTA LIQUID-FUEL BURNER Application led August 19, 1925. Serial No. 51,175.

This invention relates to new and useful improvements in liquid fuel burners particularly adapted for use in connection with heating plants, of ordinaryl constructlon, such as are commonly employed in heating homes and buildings7 and, by the use of which such a heating plant may readily and quickly be converted into a liquid fuel burning furnace.

An object of the invention is to provide a liquid fuel burner comprising a perforated fuel vaporizing pot or bowl mounted within a casing having a connection with an air supply `so that the air delivered to the vaporlzing chamber will be preheated.

A further object of the invention is to rovide a liquid fuel burner having the oil feed pipe and the overflow pipe mounted within the air trunk provided for supplying air to the burner, thereby protecting such pipes from the heat of combustion when the burner is in operation.

. as to be readily and A further object is to providefsucha structure having an auxiliary over-flow which will function should the intake to the main overflow pipe become obstructed or clogged by the accumulation of carbon therein.

A further object is to provide a liquid fuel burner having a frusto-conically shaped vaporizing pot or bowl having the walls thereof provided with suitable perforations which are so arranged that the ilow of air into the vaporizing bowl will be portion thereof thanyit is at the lower central portion thereof, thereby controlling the flow 0f air into the bowl and producing a highly combustible mixture prior to ignition with a resultant increase in the eiciency of the burner caused by ignition taking place in suspension at the top of the vaporizing bowl which has a tendency to eliminate the formation of'carbon deposits therein.

A further object is to provide a liquid fuel burner which may be efficiently and economically operated by-using the natural draft of the furnace, and which is also so constructed quickly ignited upon initial starting by the use .of a or other similar device.

A particular object of the invention, theregreater at the upper gas pilot light 7 fore, is to provide an improved `liquid fuel burner.

Other objects of the invention will appear from the following description and will be pointed out in the annexed claims.

In the accompanying drawings there has been disclosed a structure designed to carry out kthe various objects of the invention but it is to be understood that the invention is not confined to the exact features shown as various changes may be made within the scope of the claims which follow.

In the drawings: Figure l is an elevational view, partially in section, to show the general construction of the improved burner; y

Figure 2 is a plan view of Figure l;

Figure 3 is a sectional view on the line 3 3 of Figure 1, showing the relative position 0f the oil feed pipe and the over-flow pipe leading from the vaporizing chamber; an

Figure 4 is a detail sectional view on the line 4-4 of Figure light.

The novel liquid fuel burner featured in this invention comprises a casing 4, preferably cylindrical in form, having its lower end closed by means of a wall 5 as shown in Figures 1 and 3. This ported upon a standard 6 having its upper end secured to the wall 5`and its lower end adapted to rest upon the floor of the ash pit (not shown) A trunk 7 is connected to the lower portion of the casing 4 and leads outwardly therefrom through the ash pit door (not shown) The outer end of the air trunk 7 is preferably open to the atmosphere so that air may be supplied to the burner by the natural draft of the furnace or heating plant.

A split plate 8 is preferably mounted upon the trunk 7 to closethe openingorspace around the trunk where it passes through the ash pit door, it being understood that the ash pit door is preferably removed when the burner is installed. The split plate 8 may be'conveniently secured or clamped to thetrunk by means of brackets 9 and the screws or bolts 11. The outer end of the trunk ma be suitably supported by means of the plate 2 showing the gas pilot 75 casing may be sup- 8 12 having a pair of screws 13 adjustably mounted in an angle bar 14 secured to the lower portion of the plate12. By means of the supporting screws 13, the burner may be adjusted or leveled to the proper operating position.

A ,feature of this invention resides in the novel construction of the vaporizing chamber 15 provided within the casing 4. Referring to Figure 1 it will be noted that a perforated bowl or pot 16, conical in shape, is

mounted within the casing 4 and is preferably concentrically retained therein by means of brackets andY screws 17 and 18, respectively, which secure the upper portion thereof to a plate 19 having a seat 21 provided in the lower face thereof to receive the upper edge of the casing 4. lf desired, the plate 19 may be suitably secured to the walls ofthe casing 4. The lower end or bottom of the perforated or bowl 16 is closed by means of a wall 22 which is solid and functions, to provide a priming pan for the burner. An oil feed pipe 23 is connected to the lower portion of the bowl 16 as shown in Figures 1 and 3 and leads therefrom through the air intake trunk 7 to a suitable oil supply (not shown).

An over-flow pipe 24 is also mounted within i bottom wall 22 of theperforated bowl as shown in Figures 1 and 2. This plate is arranged directly beneath the discharge end of the oil feed pipe 23 and a gas pilot 20, and is I spaced from the bottom wall 22 ofthe bowl so as to provide free circulation of air between it and the bottom wall 22. This plate is heated to a very high temperature as a result of the pilot flame being constantly directed thereagainst and becausev of it being spaced from the bottom wall 22 so that the supply of air circulating in the casing 4 Will have no tendency to cool it. As the liquid fuel is discharged from the oil feed pipe 23 onto the vaporizing plate 26, the oil will immediately become vaporized and will interxnix with the air being delivered to the interior of the bowl 16 through the apertures provided in the wallthereof, thereby insuring immediate ignitionf The small plate 26 also prevents the pilot flame from directly contacting with the thin bot-tom wall 22, thereby preventing the latter from being damaged as a result of being constantly subjected to the action of the pilot flame. vThe plate 26 is supported upon ears 16, riveted to the bottom wall 22. p

Another feature of the invention resides in the novel construction of the perforated bowl 16 mounted within the casing 4. The construction of this bowl is preferably such that its lower portion is of a greater diameter than its upper portion. llt will also be noted that the apertures provided in the Wall thereof are preferably substantially equally spaced and arranged in the major portion of the wall, while at the upper portion thereof they are preferably grouped rather closely together. The purpose of thus arranging the apertures in the wall of the perforated bowl 16 is primarily to cause a smaller quantity of air to enter the bowl 16 at the lower central portion thereof, and to allow a greater quanand also to insure that combustion will take 9o place in the upper half of the perforated bowl. of air to enter the casing at its lower portion than at the upper portion thereof, the tendency to eliminate the formation of carbon is also greatly increased, caused by the vaporized fuel in the bottom of the bowl 16 being partially mixed with air before receiving thefull supply of "air delivered to the burner from the trunk 7. It has also been found in actual practice that by arranging the apertures in the wall of the bowl 16 as above del Iment with'the lower row of apertures in the wall of the bowl 16, so that should the overflow pipe 24 become obstructed and the oillevel rise inthe bottom of the perforated bowl 16 as a result of ignition failure, such oil will flow through the lower row of apertures in the wall of the bowl 16 and enter the groove 27, which, it will be noted by reference to Figures 1 and 2, is in communication with the interior of the overflow pipe 24 by means of a small orifice 28. The surplus oil will therefore flow from the groove 27 through the orifice 28 into the overflow pipe 24.. The small orifice 28 connecting the groove 27 with the over-How pipe 24 also performs an important function in prevent- By thus allowing a smaller quantity izo ing the formation of carbon in the open end of the pipe within the bowl 16. By means of the orifice 28 air will enter the pipe 24 and will flow through the open end thereof into the bowl 16. Such circulation of air through the open end of the pipe will tend to prevent carbon deposits from accumulating therein, as it is well known that air flow has a tendency to prevent formation. An orifice 29 is also provided in the oil feed pipe 23 to similarly prevent the formation of carbon deposits therein. It is to be understood that in the operation of the burner, the fuel pipe 28 is normally only partially filled with oil. Also, should carbon deposits form at the receiving end of the over-flow pipe 24 Within the burner, such carbon would form only at the extreme end of the pipe and would not extend into the pipe beyond the orifice 28.

In starting this novel liquid fuel burner oil willbe deliveredr to the perforated bowl 16 through the oil feed pipe 23 and will be discharged onto the small hot plate 26, after which the fuel oil will immediately vaporize and ignite as a result of the gas pilot light 20, or other ignition means. As soon as ignition takes place, the perforated bowl 16 will become heated, thereby causing the fuel oil inthe bottom plate 22 to become vaporized so that air entering thepbowl through the apertures in the lower portion of the wall will readily mix with the heavy vaporl thereby causing such vapor to rise within the bowl with the result that additional air will be ,heated as it rises therein. When the fuel thus partially mixed with air reaches the top or outlet of the bowl, a greater quantity of air will be supplied thereto through the band or group of apertures provided in the upper portion of the bowl, which supply of air is sufficient to produce a highly combustible mixture. Theapertures provided in the wall of the bowl 16 are of such size and are so ar.- ranged that the introduction of air into the bowl or vaporizing chamber will be increased as the `vapor rises therein, causing combustion to take place in suspension in the upper `portion of the perforated bowl or combustion chamber. It has been found in actual operation ofthe burner that bythus arranging the apertures in the wall of the bowl 16 so as to introduce a lesser amount of air into the lower portion of the bowl and a greater amount of air into the upper portion thereof,

after the fuel oil has become partially mixed' with air. that ythe formation of carbon will be practically eliminated.

It will be noted that the fuel feed pipe 23 and the over-How pipe 24 are mounted within the air supply trunk 7 thereby protecting such pipes against the intense heat of the burnervwithin the fire pot. The construction of the burner is such that it may readily and conveniently be installed in any ordinary coal burning furnace or heating plant in a said member having minimum length of time, and after once being properly installedwill require very little attention.. In installing the burner the fuel feed pipe 23 and the over-How pipe 24 are preferably connected ,to an automaticallyY operable control mechanism such as is commonly employed in connection with fuel burners of this type, and which mechanism is well known and, therefore, need not be shown in the drawings.

Having thus described my invention what I claim as new and desire to secure by United States Letters Patent is:

1. A liquid fuel burner including a casing, an air supply trunk connected therewith, a fuel vaporizing member ymounted within said casing, a fuel feed pipe and an over-flowpipe connected with said member, said vaporlzing v member having an annular groove exteriorly thereofcommunicating with said over-flow pipe to receive and conduct the'over-flow fuel from said member incase of ignition failure.

2. A liquid fuel burner having a preheating chamber, an air trunk connected therewith, a frusto-conical fuel-vaporizing member mounted in said chamber and having air intake openings therein, fuel feed and overiiow pipes communicating with said member,

an annular groove encircling said mem er and communicating with said overflow pipeexteriorly of the member to conduct the over-flow fuel from the burner.

8. A liquid fuel burner including a casing,

an air supply trunk connected therewith, a

perforated fuel vaporizing member mounted Within said casing and having its walls spaced from the wall thereof to provide an annular chamber, means providing a closure for the upper portion of said chamber, fuel feed and over-flow pipes connected with said vaporizing member, and said member having a groove eXteriorly thereof communicating with said over-How pipe and adapted to collect and conduct over-flow fuel from the burner. y

4. A liquid fuel burner comprising in combination, an air heating chamber, an air supply trunk, a fuel vaporizing member mounted in said chamber, fuel feed and over-How pipes communicating with said member, one of which pipes has an orifice in the wall thereof located exteriorly of the member and permitting the circulation of'air through the end of said pipe, to minimize the formation of carbon therein.

5. A liquid fuel burner having a preheating chamber, an air supply trunk connected with said chamber, a fuel vaporizing member mounted in the chamber, fuel feed and overflow pipes communicating with said member and normally partially filled with liquid fuel,

iso,

permitting circulation of air through the endsof the pipes, to minimize the formation of carbon in said pipes.

6. A liquid fuel burner having a preheating chamber, an air supply trunk communij eating with said chamber, a perforated fuel vaporizing member mounted in the chamber and having an annular groove communicating With the interior of the member, fuel feed and over-How pipes communicating with said member, said fuel feed pipe being adapted (to be only partially filled with liquid fuel under normal operating conditions, and said pipes 'having orices in the Walls thereof, establishing communication between the pipes and said grooves, to conduct over-How fuel from the burner and to permit circulation of air through the ends of said pipes to minimize the formation of carbon therein.

In Witness whereof, I have hereunto set my hand this 8th day of August, 1925. WILLIAM O. HORNE. 

